Masonry Veneer Curtain Walls

20 Cladding With Masonry and Concrete
Masonry Veneer
Curtain Walls
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Masonry Veneer Curtain Walls
Construction Sequence
and Essential Elements
• Shelf angle is installed on the
structural frame
• Soft joint or horizontal expansion
joint is maintained below the shelf
angle
• Flashing is installed over the shelf
angle and it should project by 1”
(25mm) and should be bent
downward at a 450 angle.
• Flashing is tucked into the backup
wall or over the slab
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Masonry Veneer Curtain Walls
Construction Sequence
and Essential Elements
• A back up wall of concrete or steel
studs covered with water resistant
sheathing panels of gypsum or
cementitious material is
constructed
• A weather barrier and air barrier
are installed over the backup wall
followed by insulation
• Brick masonry veneer wythe is
erected brick by brick or stone by
stone with conventional mortar and
tied to the backup wall by ties
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Masonry Veneer Curtain Walls
Shelf Angles &
Horizontal Joints
1.
2.
3.
Shelf angle attached to a
concrete frame with an insert
cast into the slab
Shelf angle attached to a steel
frame using clip angle and shim
plate and wedge shaped slot for
adjustments
Soft joint or horizontal
expansion joint is shown in the
typical detail of brick veneer
cavity wall with concrete block
backup wall. Joint is designed
to absorb column creep, brick
expansion, spandrel beam
deflection and dimensional
tolerances
2
3
1
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Masonry Veneer Curtain Walls
Vertical Joints
• Masonry curtain walls must
be divided vertically by
movement joints called
vertical expansion joints to
allow the frame and the
masonry cladding to expand
and contract independently
of one another
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Masonry Veneer Curtain Walls
Backup Walls and
Structural Frames
Detail and Completed Building – Brick Veneer With
Steel Stud Backup With Steel Structural Frame
• Backup walls may be of
concrete or steel studs
• Masonry cavity wall may be
installed on buildings with
structural frames of concrete
or steel.
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Masonry Veneer Curtain Walls
Prefabricated Reinforced
Brick Panel Curtain
Walls
1.
2.
2
Masons construct the
panels while working
comfortably at ground
level in a factory.
Horizontal and vertical
reinforcements are laid as
required
Panels are self-rigid and
need no structural backup
1
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Masonry Veneer Curtain Walls
Prefabricated Reinforced
Brick Panel Curtain
Walls
• These panels can be
fastened to the building in
much the same way as
precast panels
• A steel stud backup wall is
required to carry thermal
insulation, electrical wiring,
and an interior finish layer
but has no structural role
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
20 Cladding With Masonry and Concrete
Stone Curtain Walls
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Stone Curtain Walls
Stone Panels Mounted
on a Steel Subframe
• Grid-system-supported stone cladding
–
–
–
–
–
Vertical members are erected first to
transmit gravity and wind loads
The horizontal members are
aluminum shapes that engage in slots
in upper and lower edge of each
stone
Backer rods and sealants fill the joints
between the stone
Non structural back-up wall of steel
studs and gypsum sheathing is
constructed within the frame of the
building to provide air barrier,
insulation, electrical wiring and
interior finishes
Sealant joints are the weak link for
water penetration
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Stone Curtain Walls
Stone Panels and
Extruded Aluminum
Supports
2
• Stone cladding
installation in progress
1. The reddish orange
material is the weatherresistive membrane. If
properly sealed at its
seams and edges, this
product is also capable of
acting as an air barrier
2. Vertical lines struck on
the membrane mark the
locations of metal studs
in the backup wall.
Anchor fasteners must be
located over these lines,
so that they engage the
studs
2
1
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
2
Stone Curtain Walls
Stone Panels and
Extruded Aluminum
Supports
• Anchor close-up. Note the
resilient cushioning
material where the anchor
is slotted into the stone
• This image also illustrates
several construction
deficiencies:
2
1. The fasteners appear to
be offset so far to one
side of the anchor and its
shims that the clip may
not remain stable when
fully loaded by the weight
of the next panel above
2. The continuity of the
weather-resistive/air
barrier has been
interrupted by electrical
conduit routed in the
space behind the stone
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
1
Stone Curtain Walls
Monolithic Stone
Cladding Panels
• The panels are fastened
directly to the frame of the
building
• The weight is transferred to
two steel support plates by
means of edge pockets that
are cut into both sides at the
stone mill
• Each panel is stabilized by a
steel angle strut
• Joints are closed with backer
rod and sealant
• A non structural backup wall
is required
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Stone Curtain Walls
Stone Cladding on Steel
Trusses
• Sheets of stone are
combined into large
prefabricated panels by
mounting them on structural
steel trusses
• Each truss is designed to
carry wind loads and dead
load of the stone to steel
brackets that are used to
attach the truss to the
building frame
• This is a relatively costly
system
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Stone Curtain Walls
Posttensioned Limestone
Spandrel Panels
• Thick blocks of limestone
may be joined with
adhesives into long spandrel
panels and post-tensioned
with strength steel tendons
• The assembly is self
supporting between columns
• This is a relatively costly
type of panel
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Stone Curtain Walls
Very Thin Stone Facings
• Extremely thin sheets of stone may be stiffened
with a structural backing such as a metal
honeycomb and mounted as spandrel panels in
in an aluminum mullion system
• Very thin sheets of stone may be used as facings
for precast concrete curtain wall panels
• When specifying the thicknesss of stone for any
exterior cladding application, the designer
should work closely with stone supplier.
• Thin stones have been a cause of number of
failures of cladding systems
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
20 Cladding With Masonry and Concrete
Precast Concrete
Curtain Walls
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Precast Concrete Curtain Walls
Precast Concrete
Aesthetics
• Precast concrete cladding
panels can be conventionally
reinforced and be
prestressed
• They can come in variety of
sizes and surface finishes,
from glassy smooth to
rough, exposed aggregates
• Ceramic tiles, thin bricks or
stone facings may be
attached to precast panels
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Precast Concrete Curtain Walls
Precast Concrete
Manufacture of
Sandwich Panel
1.
2.
2
Ribbed surface finish
being applied to precast
concrete before the
concrete sets
Insulation can be
incorporated into the
precast concrete panel in a
sandwich panel system
1
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Precast Concrete Curtain Walls
Typical Detail of Precast
Concrete Curtain Wall
• Precast on sitecast concrete
frame
• Panels shown are full story
high containing a fixed
window. Bottom half of one
panel (1) and top half of the
lower panel (2) are shown
• The reinforcing bars are
omitted for clarity but
outline of thermal insulation
and interior finishes (3) on
the interior is shown
3
1
2
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Precast Concrete Curtain Walls
Precast Concrete
Cladding Installation
• Precast concrete
spandrel panels and
brick veneer column
covers hung off of a
cast-in-place concrete
frame structure
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Precast Concrete Curtain Walls
Precast Concrete
Cladding Installation
• End view of a precast
concrete spandrel panel
• Two polyisocyanurate rigid
foam insulation boards (1)
are visible on the back of the
panel.
• The slightly darker colored
band of insulation (2), at
slab level between the two
insulation boards, is safing,
intended to restrict the
passage of smoke and fire
between floors.
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
1
2
1
Precast Concrete Curtain Walls
Glass-Fiber-Reinforced
Concrete Curtain Walls Fabrication
• GFRC is a relatively new
cladding material
• Its admixture of short glass
fibers provides enough tensile
strength that no steel reinforcing
is required
• Panel thickness and weight are
about one quarter of those for
precast
• They can be molded into
variety of shapes
• The panels may be self-stiffened
with GFRC ribs but the usual
practice is to attach a welded
frame of light gauge steel studs
to the back of GFRC
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Precast Concrete Curtain Walls
Glass-Fiber-Reinforced
Concrete Curtain Walls Attachment
1.
2.
3.
GFRC panels can be
attached with a diagonal
brace and downrigger
GFRC panels can be
attached with angle with
oversized hole
Steel rod anchors can flex
to accommodate small
amounts of movement
between the facing and the
frame
1
2
3
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
3
Precast Concrete Curtain Walls
Glass-Fiber-Reinforced
Concrete Curtain Walls
– Joint Treatment
• Edges of the GFRC panels
are flanged to provide
surface for sealant at joints
• Edge of the GFRC panels at
transition between
components need to be
designed for receiving
membrane and cap flashing
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
20 Cladding With Masonry and Concrete
Exterior Insulation and
Finish Systems
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Exterior Insulation and Finish Systems
EIFS – Essential
Elements
• Exterior insulation and
finish system (EIFS) consists
of
–
–
–
–
Layer of plastic foam
insulation adhered or
mechanically fastened to a
backup wall
A reinforcing mesh that is
applied to the outer
surface of the foam
A base coat of a stucco
like material which embed
the mesh
An exterior finish coat of a
similar stucco like material
that is troweled over the
base coat
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Exterior Insulation and Finish Systems
EIFS – Panelized System
•
•
EIFS can be constructed
in place over a backup of
concrete masonry or steel
studs
EIFS can also be
prefabricated
A.
B.
C.
Steel studs are welded
together to make a
backup frame
Rigid sheathing is
screwed to the frame and
finished with EIFS
The finished panels are
lifted and bolted to the
building frame
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Exterior Insulation and Finish Systems
EIFS – Drained Systems
• EIFS typically is designed as
a barrier type system which
has resulted in numerous
cases of water damage in
EIFS faced buildings
• EIFS producers now market
water managed or waterdrainage EIFS
–
These systems utilize a
layer of drainage matting
behind the foam
insulation that can capture
water and conduct it to
plastic flashings and weeps
at the base of the walls
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
20 Cladding With Masonry and Concrete
Future Directions in
Masonry and Stone Cladding
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
Future Directions in Masonry and Stone Cladding
Need For Rainscreen
Systems
• Most masonry and concrete cladding
systems except brick veneer are barrier
systems
• There is no well organized system of
secondary drainage
• There are cavities behind these
systems but are interrupted by framing
and attachment components
• There have been isolated efforts to
design true rain screen details for
stone and concrete cladding systems
but more research is needed
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.
20 Cladding With Masonry and Concrete
MasterFormat Sections
For Masonry and
Concrete Cladding
CSI/CSC MASTERFORMAT SECTIONS FOR MASONRY AND CONCRETE CLADDING
03 40 00
PRECAST CONCRETE
03 45 00
Precast Architectural Concrete
Faced Architectural Precast Concrete
03 49 00
Glass-Fiber-Reinforced Concrete
04 20 00
UNIT MASONRY
04 21 00
Clay Unit Masonry
Brick Veneer Masonry
04 25 00
Unit Masonry Panels
Metal-Supported Unit Masonry Panels
04 40 00
STONE ASSEMBLIES
04 42 00
Exterior Stone Cladding
Grid-System-Supported Stone Cladding
Stone Panels for Curtain Walls
07 20 00
THERMAL PROTECTION
07 24 00
Exterior Insulation and Finish Systems
Polymer-Based Exterior Insulation and Finish System
Polymer-Modified Exterior Insulation and Finish System
Water-Drainage Exterior Insulation and Finish System
07 40 00
ROOFING AND SIDING PANELS
07 42 00
Wall Panels
Fabricated Wall Panel Assemblies
Fundamentals of Building Construction, Materials & Methods, 5th Edition
Copyright © 2009 John Wiley & Sons. All rights reserved.